Researchers say they may have found a viable biomarker that detects disease activity and treatment response in people with multiple sclerosis (MS).

The recent study, published on behalf of the American Academy of Neurology, showed a strong connection between serum neurofilament light chains and MS activity.

The researchers say the serum light chain levels correlated with new or enlarging lesions as well as with brain volume and relapses.

“Not only do neurofilament light chains correlate with everything associated with MS, but the strength is very high,” Mark Allegretta, PhD, associate vice president of commercial research for the National Multiple Sclerosis Society, told Healthline.

The scientists used samples from phase III trials. The research included 589 people with MS.

By using the baseline numbers and the number of relapses, researchers could predict neurofilament levels. These levels increased in those with disease activity.

Neurofilament light chains are used today in clinical studies but must be extracted from spinal fluid.

This new research sheds light on using chains extracted from blood samples, which are easier to extract than spinal fluid and less expensive than MRIs.

“The use of neurofilament light chains has been developing over time,” Allegretta said. “This is something we’ve been watching and continues to show more and more promise as a really viable biomarker that might have some utility in how we do clinical trials in MS.”

“These light chains have been studied at the research level in spinal levels, where you expect to find changes,” he added, “but because of improvements in technology and the assay platforms used, we can now detect it in the blood.”

“One would hope that it would correlate with other important clinical aspects of people monitored with MS as to whether or not they are responding to treatment,” he explained.

“Neurofilament light chains are a breakdown product reflecting nerve (axon) damage,” Dr. Barbara Giesser, professor of clinical neurology at the David Geffen School of Medicine at the University of California, Los Angeles and clinical director of the UCLA MS program, told Healthline.

“This study adds to the growing literature reporting that blood levels of neurofilament light chains are useful in monitoring treatment response and possibly predicting progression in persons with MS,” she added.

“Increased levels of neurofilament light chains are not specific for MS and are seen in other neurologic conditions, but they do seem to correlate with disease activity in MS, and may be able to reflect ongoing damage or treatment response that is not apparent clinically or on an MRI,” she explained. “More work is needed, as this assay is not yet widely available.”

Allegretta explains how the International Progressive MS Alliance is trying to do quicker and less costly clinical trials.

“Take, for example, measuring brain volume with MRIs. A simple blood test could be a valid readout for phase II and III trials for progressive MS,” he said.

“We are encouraged by the potential of serum neurofilament light chain (sNfL) to understand and measure progression in MS. If found effective, it could be an important breakthrough in accelerating treatments for progressive MS,” said Professor Alan Thompson, chair of the scientific steering committee for the International Progressive MS Alliance.

The new biomarker isn’t meant to replace the way things are done, but it could be used to get an earlier look at changes that are happening, Allegretta says.

He describes how the light chains could be low on one treatment and start to elevate on another treatment. This might be an indicator to change treatments, even if the person doesn’t show physical changes.